The researchers looked at 309 sun-like stars, grouped them by age, and then used the Spitzer infrared space telescope to look for dust around them. The dust glows in the infrared spectrum from the heat of the local star, and the temperature of the glow is proportional to the distance from the star.

About 10% of the stars in the Milky Way are like our Sun. If just 10% of them have rocky planets, as this study indicates, there may be a billion planets like Earth orbiting stars in our galaxy alone! Lower mass stars can form planetary systems too, of course, and there are a whole lot more of them then stars like ours. So there may be several billion terrestrial planets in the galaxy and there are hundreds of billions of galaxies in the Universe.

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Foolishness! Your DNA would actually stretch to the sun and back about 4 times!

DNA is a fine, spirally coiled thread in the nucleus of every living cell that serves as a guidebook so the cells "know" what they're supposed to do. The strands are so fine you need a high power electron microscopes to see them.

The human genome, the genetic code in each human cell, contains 23 DNA molecules each containing from 500 thousand to 2.5 million nucleotide pairs. DNA molecules of this size are 1.7 to 8.5 cm long when uncoiled, or about 5 cm on average.

You have about 10 trillion cells in your body, so if you stretched the DNA in all the cells out, end to end, they'd stretch over 744 million miles. The moon is only about 250,000 miles away, so all your DNA would stretch to the moon and back alomst 1500 times. The sun is 93,000,000 miles away, so your DNA would reach there and back about 4 times!

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Really. Or to use a more “explosive” illustration, multiply the world’s entire nuclear stockpile seven million times and detonate it. That’s also about one second’s solar output. Or put another way … well, you get the point; the Sun puts out a lot of energy.

We only avoid being incinerated by this 800,000 mile wide, 100,000,000 degree inferno because, like a light bulb, the Sun radiates in every direction. That, and the fact that we are 93,000,000 miles away, allows us to experience sunshine as a gentle blessing rather than an incinerating white-hot blast.

But where does so much energy come from? That question stumped scientists from the late 1800’s until the early 1900’s. By then science had come to realize that the earth was billions of years old, not just thousands as previously believed. But they couldn’t figure out what could have powered the Sun that energetically for so long.

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Really. The top of towers of the Verrazano - Narrows Bridge at the mouth of the Hudson river in New York City are tilted almost two inches further apart than the base thanks to the curve of the Earth's surface.

Actually, there are a lot of amazing things about that not-so-famous bridge.

When it opened in 1964, at 4260 feet it was the longest suspension bridge in the world, exceeding the Golden gate completed in 1937, by 60 feet. Today it's the longest single span in North America and the seventh longest in the world. (The longest is the 6,529 foot Akashi-Kaikyo Bridge in Japan, completed in 1998.)

The Verrazano - Narrows Bridge contains enough concrete to construct a single lane highway from New York to Washington, and if the wires that make up the suspension cables were laid end-to-end they would reach 143,000 miles, more than halfway to the moon.

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